Contour interaction under photopic and scotopic conditions

Musilová, Lenka and Pluháček, František and Marten-Ellis, Stephanie and Bedell, Harold E. and Siderov, John (2018) Contour interaction under photopic and scotopic conditions. Journal of Vision, 18 (6). pp. 1-11. ISSN 1534-7362

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In the present study, we asked whether contour interaction undergoes significant changes for different luminance levels in the central and peripheral visual field. This study included nine normal observers at two laboratories (five at Palacky University Olomouc, Czech Republic and four at the University of Houston, USA). Observers viewed a randomly selected Sloan letter surrounded by four equally spaced bars for several separations measured edge-to-edge in min arc. Stimuli were viewed foveally under photopic and mesopic luminances and between 58 and 128 peripherally for four different background luminances of the display monitors, corresponding to photopic, mesopic, scotopic, and dim scotopic levels. The extent of the contour interaction in the fovea is approximately 20 times smaller than in the periphery. Whereas the magnitude of foveal contour interaction markedly decreases with decreasing luminance, no consistent luminance-induced change occurs in peripheral contour interaction. The extent of contour interaction does not scale with the size of the target letter, either in the fovea or peripherally. The results support a neural origin of contour interaction consistent with the properties of center-surround antagonism.

Item Type: Journal Article
Keywords: contour interaction, crowding effect, mesopic, luminance, peripheral vision
Faculty: ARCHIVED Faculty of Science & Technology (until September 2018)
Depositing User: Prof John Siderov
Date Deposited: 23 Jul 2018 15:17
Last Modified: 31 Jan 2022 10:02

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